Principles of Plant Breeding (2+1)

Food Production in India

Year	Area	Production	247% growth rate
1949-50	99.20 m ha	54.92 m tonnes
1985-86	127.06 m ha	150.47 m tonnes
2000-01		220 m tonnes
2003-04		240 m tonnes

So the nation became almost self sufficient in food grains but the population is growing at an alarming rate of around 2.5% per year .Food production should also increase at least at same rate or even at faster rate to improve the nutritional status.
The 25 major food crops of the world, ranked according to total tonnage produced annually

1	Wheat	10	Oat	19	Coconut
2	Rice	11	Sorghum	20	Cotton
3	Corn (Maize)	12	Sugarcane	21	Apple
4	Potato	13	Millets	22	Yam
5	Barley	14	Banana	23	Pea nut
6	Sweet potato	15	Tomato	24	Watermelon
7	Cassava	16	Sugar beet	25	Cabbage
8	Grape	17	Rye
9	Soybean	18	Orange

It could be possible because of


• Improved crop varieties
• Better management of inputs
• Increase net cropped area

Better environment alone cannot lead to better yields from inferior varieties beyond a certain limit. The limit is set by the genetic makeup of the variety.
Eg: Tall wheat varieties give response upto 60 kg/ ha, Dwarf wheat varieties give increase yield of120 kg/ ha


• Hence, genetic makeup of plants permits considerably endless favorable changes.
  
• This continuous favorable change in the genotype of crop varieties is a must for increasing yields.
  
• So plant breeding deals with the principles and the methods required forfavorably changing thegenetic constitution of crop plants.